While mechanical stamping is highly suitable for high-throughput environments, it does have its drawbacks. No. 1 is that the process cannot be adapted quickly to changing product designs and materials in a cost-efficient manner.
In some cases, a better, more economical solution might be a coil-fed laser blanking line for high-volume production. Because laser blanking, or cutting, doesn’t require dedicated tooling, the system provides the ability to handle quick changeovers of materials and part designs to be cut.
For traditional stamping, on the other hand, it requires extensive time to produce a blanking die. In addition, die maintenance is an important consideration, especially given the increased wear rates common when blanking high-strength steels.
“The main economic advantage of a laser blanking line, in terms of cost savings, is the elimination of blanking dies,” says Justine Fonteyne, area sales manager of the Americas, Schuler Group. “This includes die investment, die maintenance and die changes during production, all of which are no longer a challenge with the integration of laser blanking technology. This makes laser blanking lines incomparable to stamping, mechanical and servo presses, and shears. Production of high-strength materials is a good example of how manufacturers benefit from laser blanking lines as they avoid wear from the dies and press with this die-free technology.”
For laser blanking, setting up a new job is a matter of loading a new coil and a new program and pushing start versus the time required for a die change when setting up a new job on a stamping press.
“You can make new blanks as soon as you change your coil as all modifications happen quickly and automatically with no hard tooling change requirements,” says Jay Finn, chief technology officer and general manager, LaserCoil Technologies LLC. “With the technology currently available today, a 2-min. last hit to first hit is achievable with the head of the next coil chasing the tail of the previous coil through the line.”
A laser setup also makes testing and last-minute orders easy to accommodate.
“Laser blanking, in particular coil-fed laser blanking, offers the ultimate flexibility as you can change the shape or add features to the blank in a matter of seconds, all right from the main operating console of the line,” Finn says. “Also, from a flexibility standpoint, parts can be nested in any coil width. A good example of an application that benefits from this is automotive service parts. When these parts are run on a press, the old dies have to be pulled from storage, and they usually require reconditioning work to make them serviceable. A master coil is then sent out to be slit to properly fit the die. This slitting process wastes a lot of material.
“With coil-fed laser blanking, any part made from the master coil is nested in the original width of the master coil,” he continues. “This eliminates the need to recondition old dies or send master coils out to be slit. This is a benefit in time as well as material utilization and inventory.”
Shankaran Shanmugabaskaran, senior vice president of sales, RDI Laser Blanking Systems, agrees about the flexibility of coil-fed laser blanking for manufacturers.
“The flexibility takes many forms, including the ability to take a drawing and seamlessly produce the cutting instructions for the laser, supporting drawing to cutting in the same day,” he says. “Whereas the stamping process requires the time to design and build the blanking die, which can require a large capital investment in the hundreds of thousands of dollars. Even with an existing die, die preparation and having the right coil can add more time and money. The flexibility also applies to being able to utilize multiple coil widths, where traditionally dies are constrained to the coil width for which they were designed.
“The laser can be quickly programmed to accommodate multiple coil widths,” he adds. “It can take only minutes to simply change the laser program for the blanks to be cut. Whereas for stamping, the entire tooling would have to be removed and changed.”
Other benefits of laser blanking over traditional stamping include product quality, scrap reduction, a smaller footprint and just an overall cost reduction.
Laser cutting produces a better blank for any downstream forming processes. When stamping high-strength steels, microfractures form along the part edges and often cause problems during subsequent processes. Often, these edges must be trimmed before moving to the next process.
“Most of the time, especially with the higher strength steels, traditional blanking dies leave microfractures all along the edge of mechanically cut blanks whereas laser cut blanks do not create this issue,” Finn says. “These defects often don’t show up during the forming die tryout process because the tryout blanks have been cut with a laser. So, when the defect occurs during production forming, the easy solution is to send the coils to a laser blanking operation.”
Laser blanking enables optimization of part nesting, part orientation, common line cutting and laser parameters to reduce costly scrap through software advancements.
“Material utilization is probably the biggest advantage of laser blanking,” Finn says. Common line cutting is actually encouraged in order to increase production rates. You can always nest parts directly adjacent to each other. This is not the case in many mechanical blanking operations due to the need to support the material properly for a quality cut.”
Another advantage of laser blanking over traditional stamping is the equipment takes up less space.
“The footprints are similar,” Schuler’s Fonteyne says, “but you increase volumetric efficiency with the elimination of the dies and the die storage and cranes, along with the press foundation or press pits. As such, the building and infrastructure costs of a die-based blanking system typically double the costs of a capital equipment investment alone. A laser blanking line eliminates a large portion of these costs. A crane to handle the coils and a forklift to take the blank stacks where they need to go is all you need.”
Shanmugabaskaran agrees, noting RDI offers a laser blanking system that takes up only a 60-ft.-by-30-ft. footprint. He adds that the RDI laser blanking system does not need any special foundations and can be placed right on the plant floor.
Although laser blanking offers slower speeds than stamping, the process still runs relatively fast, and with today’s high-power lasers that will only increase. Also, a laser blanking line can accommodate multiple cutting heads.
“Coil-fed laser blanking systems currently offer powers in excess of 8 kW, and that number is increasing with each new development,” Finn says.
To cope with the higher power lasers as well as the faster cutting speeds and production rates that result, the best material handling solutions must be determined.
“For the coil-fed laser blanking solutions that remove all of the scrap during the laser cutting process as well as companies that can reconfigure their parts so that there is no scrap,” Finn says, “traditional overhead magnetic or vacuum-style stackers with soft-piling or stop-to-drop solutions are good to use. These systems change over automatically from part to part in a matter of seconds and run at rates in excess of 100 parts/min. However, these systems can receive the blank only, so you need a system that can produce parts in that fashion.
“For systems that remove the scrap later in the process or pick the good part from the strip skeleton,” he continues, “a substantial number of robots or pick-and-place modules are required to keep up with systems running faster than 24 parts/min. These additional modules do require a significant large amount of floor space.”
Fonteyne notes that Schuler’s new scrap separation system requires no robots. The system was developed to eliminate the robots or feeders that cause bottlenecks. This also makes the process easier for the customer as they will no longer need robot programming or robot tooling.
In addition to making good parts quickly, part of today’s successful production lines is incorporating automation and data collection. This allows equipment suppliers to help their customers develop a total solution to achieve their production goals.
“Schuler has high-grade automation available to support operators, and we constantly develop new and innovative digital solutions as standard,” Fonteyne says. “One digital solution example is our check-to-flatten technology that tracks the leveling results and adjusts the leveling parameters automatically during production. Another is our track-and-trace system, which includes tracking critical production data, such as the leveling parameters mentioned and oil thickness. The system links the data to each produced part and can integrate a special marking system that tags each blank for better tracking.”
LaserCoil offers a turnkey solution that includes all of the automation and data collecting features that any customer interested in purchasing high-speed production equipment typically would require.
“We have a staff of engineers experienced in various automation projects,” Finn says. “We have produced new automation concepts using new technology as well as robotic solutions, plant information systems and data collection. All of these solutions can be customized for customer-specific needs.
“Another technology we offer is the ability to run the laser blanking system virtually,” he continues. “In a matter of minutes, a cutting program can be created and run on our virtual controller. From a production standpoint, this allows any major flaws in the program to be corrected prior to running the program on actual material. The most important aspect of this is providing salespeople, and thus potential customers, knowledge of the exact production rate of the part prior to ever laser cutting metal.”
RDI Laser Blanking Systems also helps customers incorporate automation and data collection. “Customers want to integrate their systems, so an order or job from their ERP feeds into the laser system with the upcoming workloads.” Shanmugabaskaran says. “With integrations to their data warehouses, ERP system and other third-party tools, they can utilize their existing platforms to view the data and help make decisions to perform better and get closer to maximizing their ROI. Or, built-in tools on the HMI screen are available to review the data. And smart sensors and built-in intelligence can improve operating efficiency and reduce unexpected downtime, such as by alerting when maintenance is needed.”
As far as laser blanking’s place in the metalforming industry, Fonteyne shares that Schuler has sold more than 40 blanking lines since 2015. In total, 15 laser blanking lines have been sold worldwide, and five laser blanking lines have been sold in North America.
“Currently, Schuler is the only supplier with the experience and capability to run high-volume serial production. Our lines are developed for high-volume production of outer body car and structural parts, and we achieve up to 6 million parts per year,” she says. “However, the laser blanking lines are very flexible and can be used for any kind of strip material. Schuler provides customized, customer-centric solutions and guides the customer through their specific production needs per business case.”
LaserCoil’s base automotive product is designed to be easily retrofit into an existing laser blanking line by replacing the press and utilizing the existing coil line and stacking equipment.
“Toll processors and service centers utilize this technology not only for regular production work, but also as a backup for all other blanking and cut-to-length operations within an organization,” Finn says. “The flexibility and the reliability of these systems help ensure companies never miss a delivery.”
Shanmugabaskaran sums it up this way. “Service centers utilize our technology because of the minimal floor space requirements and to further expand their offerings to customers. Where traditionally they provided slit coils for mechanical blanking or sheets to feed table lasers, now they can provide the end customers with the final blank. Toll processors can quickly adapt to customer needs as well. We are seeing more interest these last few months from customers running stamping lines, especially those supporting the EV industry that are looking to eliminate dies and produce a high-quality, microfracture-free part.
“Coil-fed laser blanking can benefit manufacturers using multiple processes to produce their parts – this technology combines many into one integrated process,” he summarizes. “We have seen an increase in OEM customers with lower volume part production needs consolidating their operations. They can also nest a kit of parts quickly and continuously as they focus on just-in-time production. They want to avoid building to stock and this technology helps them adapt and be flexible to support the changing production demands of their customers.